Cells become cancerous when their genotype or phenotype alters in a way that there is uncontrolled growth which is not subject to the confines of the normal tissue environment. One or more genes is mutated, amplified, deleted, overexpressed or underexpressed. Chromosome portions can be lost or moved from one location to another. Some cancers have characteristic patterns by which genotypes or phenotypes are altered.
A variety of agents treat cancers. Cancers of the blood and bone marrow often are treated with steroids/glucocorticoids, imids, proteasome inhibitors and alkylating agents. Cancers of other tissues often are treated with alkylating agents, topoisomerase inhibitors, kinase inhibitors, microtubule inhibitors, angiogenesis inhibitors or other agents.
One of the continued problems with therapy in cancer patients is individual differences in response to therapies. Some patients respond to one therapy better than another, presenting the potential for a patient to follow multiple therapeutic routes to effective therapy. With the narrow therapeutic index and the toxic potential of many available cancer therapies, such differential responses potentially contribute to patients undergoing unnecessary, ineffective and even potentially harmful therapy regimens. If a designed therapy could be optimized to treat individual patients, such situations could be reduced or even eliminated and there may be more focused, successful patient therapy overall.